As is known in the prior art, an in-vehicle antenna may be installed as an element of a Bluetooth® module of a vehicle navigation apparatus. The in-vehicle antenna needs to be reliably fixed to an installation counterpart, such as a casing of a device, so that communication with Bluetooth®-enabled devices used within the vehicle can be maintained on a constant basis.
As described in JP2013-201511 A and JP2004-236184 A, a sheet metal antenna fabricated through sheet metal working of a metal plate is often used for this type of antenna in order to reduce costs. The antenna of this type is generally installed in a casing by screwing the sheet metal antenna onto the casing. However, since screwing involves a large number of steps, it is desirable to implement installation by a simpler method to reduce costs of the in-vehicle devices. The in-vehicle antenna is further required to stably maintain an installed state during vibration and impact caused by both operation of a vehicle engine and vehicle motion. The sheet metal antenna has a ground part which comes into contact with a ground part provided in the installation counterpart, and the mechanical contact and electrical connection between the ground parts needs to be stably maintained even when these vibrations and impacts are applied thereto.